Building block toy stool



FIG. 1 is a perspective view of a building block toy stool, showing my new design.

FIG. 2 is a front elevational view thereof;

FIG. 3 is a right side elevational view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a left side elevational view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof. 

I claim the ornamental design for a building block toy stool, as shown. 